[v0][PATCH 1/1] powerpc/book3e: disable interrupt after preempt_schedule_irq

[Tiejun Chen]

In preempt case current arch_local_irq_restore() from
preempt_schedule_irq() may enable hard interrupt but we really
should disable interrupts when we return from the interrupt,
and so that we don't get interrupted after loading SRR0/1.

Signed-off-by: Tiejun Chen <tiejun.chen at windriver.com>
---
 arch/powerpc/kernel/entry_64.S |   13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index e9a906c..4e1de34 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -662,6 +662,19 @@ resume_kernel:
 	ld	r4,TI_FLAGS(r9)
 	andi.	r0,r4,_TIF_NEED_RESCHED
 	bne	1b
+
+	/*
+	 * arch_local_irq_restore() from preempt_schedule_irq above may
+	 * enable hard interrupt but we really should disable interrupts
+	 * when we return from the interrupt, and so that we don't get
+	 * interrupted after loading SRR0/1.
+	 */
+#ifdef CONFIG_PPC_BOOK3E
+	wrteei	0
+#else
+	ld	r10,PACAKMSR(r13) /* Get kernel MSR without EE */
+	mtmsrd	r10,1		  /* Update machine state */
+#endif /* CONFIG_PPC_BOOK3E */
 #endif /* CONFIG_PREEMPT */
 
 	.globl	fast_exc_return_irq
-- 
1.7.9.5